title: Current controversies in prenatal diagnosis 2: Down syndrome screening: is ultrasound better than cell-free nucleic acids in maternal blood?
authors.affiliation: Department of Obstetrics and Fetal Medicine, Leiden University Medical Center, Leiden, The Netherlands. J.M.M.van_Lith@lumc.nl
authors.forename: Jan M M
authors.initials: JM
authors.lastname: van Lith
authors.forename: Beryl R
authors.initials: BR
authors.lastname: Benacerraf
authors.forename: Simcha
authors.initials: S
authors.lastname: Yagel
mesh_terms: D001774:Blood Chemical Analysis / Q000379:methods / Q000592:standards; D002474:Cell-Free System / Q000737:chemistry; D032921:Consensus; D034462:Dissent and Disputes; D004314:Down Syndrome / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008403:Mass Screening / Q000379:methods*; D009035:Mothers; D009696:Nucleic Acids / Q000032:analysis / Q000097:blood*; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods / Q000639:trends*; D016216:Ultrasonography, Prenatal / Q000592:standards
chemical_list: D009696:Nucleic Acids